Polish prosecutors plan to question filmmaker Roman Polanski after they received a request for his extradition to the United States over a 1977 child sex crime conviction, the prosecutor-general's office said Wednesday.

Jerzy Stachowicz, a lawyer for the director, told Reuters, "We confirm that the American side made an official request for the extradition of Mr. Roman Polaski. Currently this request is on its way to the prosecutor's office in Krakow. We do not know the content of the application, so we cannot comment on the merits."

Polanski, who was born to Polish parents but lives in France, has been spending time in the southern Polish city of Krakow, where he is planning to shoot a film.

In October last year, prosecutors in Krakow interviewed Polanski in connection with a U.S. warrant over the 1977 conviction. They said that there were no grounds to arrest him and that they would await a U.S. extradition request before deciding on any further steps.

"There is no doubt that the issue will be brought in front of an independent court in Krakow. Any substantive arguments that we have prepared will be presented in court," Jan Olszewski, another lawyer, told Reuters.

The filmmaker pleaded guilty in 1977 of having unlawful sex with Samantha Geimer, 13, during a photo shoot in Los Angeles, fueled by champagne and drugs.

Polanski served 42 days in jail as part of a 90-day plea bargain. He fled the United States the following year, believing the judge hearing his case could overrule the deal and put him in jail for years.

In 2009, Polanski was arrested in the Zurich, Switzerland, on the U.S. warrant and was placed under house arrest. He was freed in 2010 after Swiss authorities decided not to extradite him to the United States.

His lawyers have been seeking assurances from the Polish authorities that he can travel freely back and forth to Krakow to work on the film project, about the 19th-century Dreyfus affair, without risking another arrest.